The author believes that web application business logic vulnerabilities will be under increasing attention in near future. Although input validation vulnerabilities (XSS, SQLI) are in overwhelming majority nowadays, many automated approaches have emerged that deal with them. On the contrary, there are no known approaches (and methodologies for security experts) to classify or even detect business logic vulnerabilities. Besides, business logic flaws usually expose web application to great risks (according to OWASP Testing Guide). My proposal is to create a systematic approach that addresses business logic vulnerabilities.